Most, if not all, conventional ocular formulations for treatment of various eye disorders contain one or more preservatives in order to prolong-shelf life as well as to prevent possible microorganism contamination. Unfortunately, it has been found recently that preservatives themselves cause undesired side-effects. See, for example, Alberto Aguayo Bonniard et al. in “Ocular surface toxicity from glaucoma topical medications and associated preservatives such as benzalkonium chloride (BAK),” Expert Opin Drug Metab Toxicol., 2016 Jul. 18:1-11 (the “Bonniard et al. Reference”). As stated in the Bonniard et al. Reference, use of ocular formulations having a preservative “ . . . are counterbalanced by the adverse effects of corneal and conjunctival toxicity.”
Therefore, there is a need for ocular formulations that are free of preservatives.